Guidelines for postoperative rehabilitation after knee arthroplasty Postoperative rehabilitation exercises should pay attention to the protection of the wound to avoid contamination, if the wound is exposed, the dressing should be sterilized and changed immediately. Exercise should start from a small amount and gradually increase or decrease according to the reaction (general condition, fatigue, localized swelling and pain in the knee joint, etc.) after the exercise and the next day. It is preferable that no localized pain or swelling of the knee occurs after exercise, and if it does, appropriate measures should be taken to relieve it within a few hours, and it should not continue until the next day. Distribute the amount of exercise evenly and take short breaks. It is more effective to exercise for short periods of time several times a day than to exercise for long periods of time every other day. Adjust the intensity, duration and mode of exercise at the right time according to the needs of different stages of rehabilitation and functional recovery. If the pain before or after exercise is serious or sensitive to pain, some warm therapy can be used, and anti-inflammatory analgesics or painkillers can be used in small quantities. Elderly people should urinate and defecate before exercising, and avoid exercising half an hour to an hour after waking up from sleep or immediately after getting up. Exercise should wear loose clothing and pants and non-slip shoes, it is best to have someone to assist in the protection, and be properly encouraged to work together with efforts. A combination of exercises to increase knee mobility and to increase muscle strength should be maintained for a long period of time, even if normal levels are achieved. Perioperative rehabilitation exercises, mainly during postoperative hospitalization, can be carried out in several stages according to the postoperative physical recovery status. (Beginning stage, intermediate stage, progressive stage, resumption of activities stage) Because of the surgical trauma and a certain amount of intraoperative blood loss, the patient is weaker on the first postoperative day, and the pain of the wound is also more obvious, the gastrointestinal function caused by anesthesia has not been fully recovered can not eat, and at the same time, the blood accumulation in the joint cavity still needs to be drained out through the retained drainage tube. Therefore, the patient is mainly sedated. The ankle to above the knee joint is wrapped with an elastic bandage with slight pressure, and an ice pack with cold compresses to reduce bleeding and eliminate swelling. Since even normal people tend to have mild knee flexion at rest, if the soft tissues of the back side of the knee are tight, the heel should be elevated to keep the knee in the straight position to prevent knee flexion contracture in the future, and sandbags should be used for compression between training sessions and at night to prevent flexion with a knee brace or an extensor cast, which should be used continuously for 6 to 8 weeks after surgery. As the muscle contraction and expansion of the lower limbs is like a pump that constantly squeezes blood back to the heart, complete inactivity of the affected limbs after the surgery can cause the blood of the lower limbs to stagnate and swell, resulting in deep vein thrombosis, and dislodgement of the thrombus can result in life-threatening pulmonary and cerebral infarctions. At the same time, complete inactivity can make the muscles and joints lose elasticity, affecting the recovery of limb and joint functions after surgery. Therefore, the lower leg should be slightly elevated on the first to third days after surgery, and the following rehabilitation exercises should be done: ① Passive exercises (completed by the accompanying personnel under the guidance of medical personnel) Massage the affected limb from the foot to the thigh for 10 minutes every 2 hours Massage the affected limb from the foot to the thigh for 10 minutes every 2 hours Dorsiflexion of the ankle joint (alternating with the massage of the lower limb) and 10 minutes of activity every 1 hour are avoided in this stage. CPM exercises should be avoided at this stage because they may increase intra-articular hemorrhage. ② active exercises (completed by the patient) muscle isometric contraction exercises (and passive exercises at intervals): foot force to do the up hook and step down movement, every 1 hour 10, each action lasts 3 seconds healthy knee flexion, the affected knee is fully straightened to do the bed pressure action, at this time, quadriceps muscle contraction, knee spreading, the patella can be slightly up and down movement, every 2 hours of practice 1 group, repeat 30 times, each time lasts 10 to 15 seconds Through this stage of exercise should be achieved: basic elimination of swelling of the affected limb thigh, calf muscles can be coordinated to make muscle contraction movements rely on the calf gravity, the knee joint passive free flexion without serious discomfort The patient can eat normally, physical strength gradually recovered, wound pain began to reduce the blood in the joints of the drainage tubes have been removed, the affected limb swelling is gradually eliminated, you can sit up in bed. At this stage, you can continue the exercises of the previous 3 days, but gradually over to fully active exercises. Increase the following exercises: ① Active exercises Lift the thigh up and bend the knee, 5~10 times every 2 hours, or lie on your back next to the bed. Turning on your side with the affected limb on top, perform gravity-defying knee flexion and extension, 5-10 strokes every 2 hours. With the help of a chaperone, sit on the edge of the bed with the lower legs naturally hanging down on the edge of the bed. If the pain is severe, put a stool next to the bed and rest your feet on the stool. Or lie on the bedside, hang the affected side of the lower leg under the edge of the bed, and adjust the degree of knee flexion through self-adjustment of the position of the hip joint and the angle of abduction, in order to complete the active flexion of the knee under self-control, and the angle is gradually increased. Sag for about 10 minutes every 2 hours. After getting used to natural prolapse, sit on the edge of the bed and do the following exercises: the healthy side (or one side) foot and calf press on the affected side (or the other side) ankle, and do a downward and leisurely pressure. The healthy side (or one side) foot hooked on the affected side (or the other side) heel, to help the affected side (or the other side) calf to do upward movement; or a bandage tied to the foot, the other end of the patient’s hand, self-traction to make the calf up, knee straight. Alternate between the two, practicing 20-30 minutes every 2 hours to enhance joint range of motion exercises (ROM exercises). At this stage, you can get out of bed and sit on a stool or do adaptive standing with the help of a chaperone (after the trauma reaction period). Knee replacement without cemented fixation should be done 5-6 weeks after surgery. ② Passive exercises If you have the conditions, you can start CPM exercises, starting from 20 ~ 30 °, gradually increase the angle, 3 ~ 4 times a day, 30 minutes / times. The advantage of this exercise is that the patient is in a relaxed state when practicing, and it is easier to overcome the muscle tension caused by pain during activities. Several exercises can be performed alternately, do not worry about the swelling or purple congestion of the calf and foot surface caused by the sagging of the affected limb, which will gradually disappear with the postoperative recovery exercises. Through this stage of exercise should be achieved: to strive for the knee joint passive flexion to 90 °, and can be fully straightened (passive) can adapt to the bench and standing state According to the recovery situation to continue the previous stage of exercise, and can further increase the following exercises. ① Straight leg raising exercises in bed, 30° can be raised to ensure that the knee joint is straight and the back is spread, hold on for 5~7 seconds, repeat 30 times, practice 3~4 times a day. Pillow can be padded first to help, and gradually reduce the height of the pillow. Avoid lying on the side of the adductor leg raising (straight leg raising exercise). ② Hold the railings to do squatting exercises, squatting and insisting on 5 to 7 seconds, 3 to 4 times a day, 30 times each time, gradually increase the degree of squatting. ③ Progressive knee and ankle flexion and extension exercises Slowly and simultaneously lift the heels until the toes hit the ground, then put them back until the heels hit the ground Alternately practice the above movements with one foot on the toes and one on the heels, alternating between pulling both feet toward the hips in turn. To slide your entire foot across the floor, be sure to press hard on the floor and feel the muscles tense up. Bring one leg forward and hook your toes. Allow the leg to straighten out completely and let the ball of the foot rest completely on the floor as you pull the leg back out Extend one leg a short distance off the floor. Hold for 7 seconds and slowly lower your leg so that your heel is on the ground. Then put your foot on the ground and slowly pull your leg back. Practice 3 to 4 sets of 30 repetitions per day. ④Exercise ③ can also be practiced in bed and combined with exercise ①. ⑤Practice walking on a flat road with a walker under the guidance of a chaperone, with a knee weight of about 10 kilograms (weighing), and practice 3-4 times a day for 10-20 minutes each time. The above exercises should be carried out on your own or under the guidance of medical personnel by reasonable arrangement and alternately during the day. Through this stage of exercise, the following should be achieved: active knee flexion of 90° or more, active straightening and sitting.